A slot is a position within a group, series, or sequence. It may also refer to:

In casinos, a slot is a machine that accepts cash or paper tickets with barcodes as payment for credits that can be redeemed for real money. Players activate the machines by pressing a lever or button (either physical or on a touchscreen), which then spins one or more reels that display symbols. When a winning combination appears, the player receives a payout according to the machine’s paytable. Most slot games have a theme and feature symbols aligned with that theme.

Unlike traditional mechanical slot machines, modern digital slots are operated by computer programs that generate random results for each spin. These programs allow for a huge variety of gameplay and bonus features, such as free spins, risky card games, and jackpots. Many modern slot machines are also equipped with sensors that detect tampering, such as the door switch being flipped or a malfunctioning reel motor. These sensor systems, often called tilt switches, are designed to prevent unauthorized access to the machines and protect the integrity of the machines’ internal components.

In aviation, a slot is an authorization for an aircraft to take off or land at a specific airport on a given day and during a specified time period. Slots are used at busy airports to prevent repeated delays caused by too many flights attempting to take off or land simultaneously. The amount of available slots at each airport is managed by a central control system, which assigns slots to each flight based on its schedule and other factors.